First Grow! Box Built! Help with lights

[tipper]

First I would like to say hello to everyone!

So here we go
I built a 2x2x4 Cab It has 2 Passive intakes with a 80Cfm bathroom fan for exhaust. I will take some pictures as soon as my battery charges.

So I'm Looking for some help with lighting
Im either going to purchase a 400w hps or 250 w hps any help would be greatly appreciated.

Everyone says I will have major heating issues with the 400w but I plan on purchasing a cool tube. Keep in mind this will be in my loft which is not insulated and it does get rather chilly here in the winter.

 

[tipper]

Bump

 

[raiderdave]

first off nice build.i would go with a 250w 2x2 thats not to big 250 will be perfect for 3-4 med plants or 9 small plants if you go with 250 might not need cool tube 400 will need it and a bigger exhaust fan imo the 80cfm will not due

 

[CannaRebel]

My take is that whenever you are lmited on space, you need to get the most out of your build, so i would ignore the heating issues this time and install a 400W Cooltube lamp. if it gets chilly there in the winter then all the better. If stiill you will have heat problems, then you can compensate with better CFM exhausts.

 

[TorturedSoul]

First I would like to say hello to everyone!

So here we go
I built a 2x2x4 Cab It has 2 Passive intakes with a 80Cfm bathroom fan for exhaust. I will take some pictures as soon as my battery charges.

So I'm Looking for some help with lighting
Im either going to purchase a 400w hps or 250 w hps any help would be greatly appreciated.

Everyone says I will have major heating issues with the 400w but I plan on purchasing a cool tube. Keep in mind this will be in my loft which is not insulated and it does get rather chilly here in the winter.

Is that white glossy? Flat bright/brilliant/titanium white works better.

If it was me, what I would do is:

Take that low-CFM fan off of the light run and use it strictly for a cabinet vent. Get a separate blower/fan for the light run. To complete the run, set up intake for the light run that goes through the wall and into the light (use a sealed reflector, lol). If possible, keep them separate - IOW, pull air from another room/location to cool the light and exhaust it into the same location (or a third one) so that it doesn't mix with the air that vents/cools your cabinet. The cabinet will be cooler. As the weather cools (or if you run CO2) you can cycle the cabinet exhaust instead of running it 100%. As it continues to cool, you have the option of slowing your light blower a little (watch for canopy-temperature increases). As it cools still more, you could set up something to mix/bleed some of that air into the cabinet for heating. You'd introduce that air into the bottom of the cabinet, maybe even directly under the reservoir, as needed. Use supplemental heating on the colder nights.

When you aren't recirculating a portion of the light run back into the cabinet for heating, it is a separate system and the exhaust will be hot - but not smelly. The only smelly air will be that pulled through your actual cabinet itself with the cabinet fan and as it won't be as hot (or as much air) as a single vent system, it will allow your carbon filter to work better and longer. The air from the light will be heated but just smell like... hot air, lol, so it can be dispersed easier and with less/no treatment.

It's a win/win.

Doesn't hurt to insulate the reflector and its duct run either. Use something that will stand up to high heat (in the case of catastrophic fan failure or operator error). Insulating the cabinet is a given.

Completely scent-free heated air from the light-run could even be used for heating another space in the cooler months. Remember, it's only waste-heat... if you don't use it. (Triple-check your seals so that it'll stay scent-free.)

Grab a 400-Watt Lumatek ballast and a set of good bulbs. Use a 250-watt MH bulb for vegetative. The Lumatek is dimmable and allows for some upgrade to the size of your cabinet. It is also efficient and (for its wattage) quite bright. Make sure your light run's blower is up to snuff. The full 400-watt output might be too much without excellent ventilation and cooling and you'd really need to add supplemental CO2 to take advantage of it in such a small space, but it will be there when you need it without purchasing an upgraded ballast later. Alternatively, a 250-watt Lumatek would work now and could be used as a vegetative ballast later if, instead of increasing the size of your cabinet, you instead add another (larger) one strictly for flowering.

YMMV.

 

[SnowBender]

tipper,

TS just hooked you up on a solid setup!

Is that in the attic?
Whats the highest and lowest ambient temp in the room?
Whats the intake plan? Every exhaust should have an equal (or lager) intake.